The presently described technology relates to a jet engine. In particular, the present technology relates to jet engines for an aircraft.
Jet engines for an aircraft often have generator units that are arranged on at least one of the turbine shafts. The generator units are arranged in order, through linking, to tap mechanical power and convert it into electrical power. In this arrangement, the jet engine can be operated in connection an aircraft, or as a stationary jet engine. The electrical power generated can be used to facilitate operation of different electrical equipment of the engine and the aircraft. Recent developments in this field indicate that the amount of electric power demanded by the engine and the aircraft is increasing due to the increased electrification of various assemblies. These various electrical assemblies presently use mechanically driven devices, such as fuel pumps or hydraulic pumps, and are often driven using device carriers, or “gearboxes.” In the future, however, many of these devices will be able to be driven electrically. Additionally, the amount of electrical power required for use on board the aircraft is continually increasing.
The jet engine of the present technology particularly involves a fan engine designed as a two-shaft engine, where the fan serves as a blower causing preliminary compression of the air flowing into the engine as well as by-pass flow around the hot exhaust stream.
Also known in the art are single-shaft systems having multi-axle compressors placed on the front side and in the rear area have a single or multiple axle turbine. A jet engine of this general type is generally described in United States Publication No. 2002/0122723 A1 as having a generator integrated in the high pressure compressor of the jet engine. The jet engine has compressor stages that are shrouded, whereby an electrical generator is located outside the shroud. It consists of a stator, which comprises an electrical coil and a rotor that is connected to the engine shaft in such a way that is executes a rotation movement. The rotor arrangement executes a rotation movement inside the stator and induces an electrical voltage in the stator coil. In this case, the rotor elements are arranged on the outside on the blade elements of the high pressure compressor and extend radially outward into the stator of the generator.
Another arrangement of a generator inside a jet engine is described in U.S. Pat. No. 6,378,293 B1. In this patent, a jet engine is described as having a number of shafts, each of which connects the compressors to the assigned turbines of the jet engine. The generator for generating the electrical power is fed by electromagnetic bearings and delivers a partial power for supplying the aircraft. The generator is arranged far from the respective electromagnetic bearings and designed as a separate unit. The drive of the generator is produced by the connection of the low pressure shaft of the jet engine. In this case, the fluid connections must generally be produced using complicated connecting devices for connecting cable and/or fluid lines and must be disconnected again upon removal. The result is disadvantageous, as it leads to an increase in maintenance and assembly effort, which also causes a considerable increase in costs of initial placement assembly, maintenance and repair.
Problems occur with the presently known generator to shaft of the jet engine arrangements because the installation location of the generators are difficult to access, thereby causing problems, in particular in the area of the high pressure compressor, due to the limited installation conditions. Even with a one-sided attachment of the generator to the low pressure shaft, the installation options, the maintenance and production of corresponding fluid, and the mechanical and electrical connections of the generator with the jet engine and/or with the aircraft are extremely difficult. Because of this, the maintenance effort and the assembly effort are considerably increased, making replacement of the generator very complicated. During assembly or disassembly of the generator, the generator must first be mechanically loosened from the low pressure shaft, whereby both electrical and fluid connections must generally be loosened using complicated connecting devices like cables and pressure lines. The mechanical connection between the engine shaft and the generator in most cases comprises a shaft coupling, which also requires a complicated installation and/or removal.